Cystic fibrosis no barrier for Nathan Charles as he prepares for Test debut

Wallabies hooker Nathan Charles has "defied science and logic" to be named to make his Test debut for Australia against France this weekend.

Charles has cystic fibrosis – a genetic disease that significantly affects the lungs and the pancreas – and is the only known professional athlete in the world with the condition playing a contact sport.

Force back-rower Ben McCalman starts at No.8 in place of Palu (ankle), who is expected to return for the final Test in Sydney on June 21, while Rebels prop Laurie Weeks and second-rower Luke Jones come onto the bench. McKenzie left the back line untouched.

McKenzie said he expected a much more direct France if they name, as expected, imposing back-rower Louis Picamoles and 120-kilogram centre Mathieu Bastareaud.

"They'll be direct and purposeful; they have the types of players who can do that in the forwards and the backs," he said.

"I expect they'll be pretty excitable and determined at the front of the game. We'll have to meet fire with fire and impose ourselves."

The Wallabies have been gradually adding more territory to their attacking game plan. Centre Matt Toomua has taken the bulk of kicks for touch, while Bernard Foley and Nic White shared the goal-kicking.

McKenzie said it was an area of the game he was pleased with in the Wallabies' 50-23 first Test win.

"It's about balance – everyone would like you to run the ball all the time but you need to be able to manipulate the back three," he said.

"When you kick you change two things – you change the back three and where they stand, and you also change the enthusiasm of the defensive line, so you need to be able to play around with both of those things.

"If you do that well, it makes the running opportunities better."

The Wallabies' scrum came in for special attention in camp this week after France's late penalty try in Brisbane.

NSW prop Paddy Ryan paid the price for that with demotion out of the match 23, but Horwill said the entire pack needed to improve.

"[France] have a little bit more nous in what they're doing and they try to work you in different ways," he said. "They get a lot of confidence when their scrum or maul are going forward."

"That last scrum of the game wasn't good enough, so we had a big hit-out [on Tuesday] to rectify those issues."